Q.6 The traffic lights at three different road crossings change after every 48 seconds, 72 seconds and 108 seconds respectively. If they change simultaneously at 7 a.m., at what time will they change simultaneously again?
LCM = 2× 2× 2×3×3×2×3 = 432
432 sec = 7 min 12 sec
Hence, lights will change together after every 432 seconds
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